Earlier quoted context omitted.
Right, it's more that our society has decided that humans have no value until they're at least 18 (hell, with college degree requirements that age is approaching 22), so we have to store them somewhere until then.
Does it make your nebulous conspiracy theory more believable or less believable when you consider that the age of 18 is generally when people's bodies have reached full maturity? Personally, if my 22 year old self travelled in time three years backwards to meet 17 year old me, and then travelled 20 years forward to present day to me current me, I have no doubt 18 year old me would the odd man out in this triplet.
Does it make his nebulous conspiracy theory more or less believable that you somehow think the age at which we stop warehousing kids actually has nothing at all to do with physical maturation?